The present invention relates to a vehicle door lock assembly and, more particularly, to a vehicle door lock assembly having one-motion opening function and one-step locking function.
In the one-motion opening function state, the door which is held in the locked state can be unlocked by manual operation of a door inside handle so that the door in the unlocked state is capable of being opened.
In the one-step locking function state, when the door is unlocked and held opened, the door can be locked and closed by manually closing the door and by manually operating a door inside locking operation member without also manually operating a door outside handle.
A conventional door lock assembly of this kind is disclosed in Japanese Utility Model Publication No. 31960/1983. This known assembly uses an opening lever that is rotated by manually operating either a door inside handle or an outside handle. This actuates a latch mechanism via a lift lever. A lock operation member is manually operated to rotate a locking member. This disengages the opening lever from the lift lever.
In this conventional assembly, the lift lever is divided into first and second lift levers. The first lift lever can engage the locking member. An inside lever can engage this first lift lever. The second lift lever is linked to the latch mechanism. The first and second lift levers can be engaged with each other in a direction to actuate the latch mechanism.
In this structure, when the locking member is in its locked position, if the inside handle is manually operated to rotate the inside lever from its initial position, the inside lever engages the first lift lever, which in turn rotates in a direction to actuate the latch mechanism. The first lift lever engages with the locking member and with the second lift lever. This rotates the locking member from its locked position to its unlocked position. The second lift lever rotates in a direction to actuate the latch mechanism, thus unlatching the latch mechanism. This is so-called one-motion opening function. When the locking member is in its locked position, if the latch mechanism is actuated, the second lift lever rotates in response to the operation of the latch mechanism. However, the rotation of the second lift lever is not transmitted to the first lift lever. Therefore, the locking member is not rotated to the unlocked position. This is so-called one-step locking function.
The aforementioned conventional assembly requires that the lift lever be split into the first and second lift levers. Therefore, this lock assembly has a large number of components and is disadvantageous in terms of the number of assembly steps and cost. Furthermore, since the lift lever is split into the first and second lift levers, some clearance must be defined between both lift levers, taking account of their dimensional errors. This clearance introduces delay to the timing at which the latch mechanism is actuated in response to operation of the inside or outside operation handle. This might deteriorate the operator's feeling in operating the assembly.